The present invention relates to processes and apparatuses for forming multi-layer golf balls, and more particularly to processes and equipment for forming multi-layer golf balls having one or more deep dimples that extend through the outer cover layer to and/or into one or more layers or components thereunder. Preferably, the deep dimples are at least twice the depth of conventional dimples, more preferably, three or four times the depth of conventional dimples.
A number of two-piece (a solid resilient center or core with a molded cover) and multi-layer (liquid or solid center and multiple mantle and/or cover layers) golf balls have been produced. Different types of materials and/or processing parameters have been utilized to formulate the cores, covers, etc. of these balls, which dramatically alter the balls"" overall characteristics. In addition, multi-layer covers of different materials have also been formulated in an attempt to produce a golf ball having the overall distance, playability and durability characteristics desired.
For certain applications it is desirable to produce a golf ball having a very thin cover layer. However, due to equipment limitations, it is often very difficult to mold a thin cover. Accordingly, it would be beneficial to provide an apparatus and technique for producing a relatively thin outer cover layer.
Moreover, retractable pins have been utilized to hold, or center, the core or core and mantle and/or cover layer(s) in place while molding an outer cover layer thereon. The pins sometimes produce centering difficulties and cosmetic problems (i.e. pin flash, pin marks, etc.) during retraction, which in turn require additional handling to produce a golf ball suitable for use and sale. Additionally, the lower the viscosity of the mantle and/or cover materials, the greater the tendency for the retractable pins to stick due to material accumulation, making it necessary to shut down and clean the molds routinely. Accordingly, it would be desirable to provide an apparatus and method for forming a cover layer on a golf ball without the use of retractable pins.
One aspect of the invention is to provide equipment and methods for forming a golf ball having a dimpled cover that is thinner than traditional cover layers. One or more deep dimples that extend through the cover layer to and/or into the core are also present in the cover layer.
Another aspect of the invention is to provide equipment and methods for forming a golf ball having one or more dimples in an outer cover layer that extend to, and/or into at least the next inner layer of the ball. Preferably, the deep dimples are at least twice the depth of conventional dimples, and more preferably, three or four times the depth of conventional dimples.
Still another aspect of the invention is to provide novel molding equipment that simplifies manufacturing of golf balls and components thereof.
The present invention provides, in a further aspect, a molding apparatus for forming a golf ball defining a plurality of dimples along its outer surface and at least two deep dimples accessible from the outer surface. The molding apparatus comprises a first mold half defining a hemispherical first mold surface. The molding apparatus also comprises a second mold half defining a hemispherical second mold surface. The first and the second mold surfaces have a plurality of raised regions that form dimples along the outer surface of the golf ball. The molding apparatus is further configured such that the first mold surface and the second mold surface each include at least one outwardly extending protrusion that forms the at least one deep dimple along the outer surface of the golf ball. The outwardly extending protrusion has a height at least twice that of the height of any of the plurality of raised regions.
In another aspect, the present invention provides a molding apparatus adapted for forming a golf ball core or intermediate ball assembly having at least two recessed regions defined along an outer surface of the golf ball core or intermediate ball assembly. The molding apparatus comprises a first mold defining a generally flat first mating surface, a first concave hemispherical molding surface, and at least two projections located along a circular edge extending between the first mating surface and the first molding surface. The molding apparatus further comprises a second mold defining a generally flat second mating surface, a second concave hemispherical molding surface, and at least two projections located along a circular edge extending between the second mating surface and the second molding surface. The first and second molds are adapted to be placed in a molding configuration in which the first mating surface contacts the second mating surface, and the first molding surface and the second molding surface are aligned with each other to form a generally spherical molding chamber. The at least two projections of the first mold are aligned with the at least two projections of the second mold which together, serve to form the at least two recessed regions defined along an outer surface of the golf ball core or intermediate ball assembly when the core or assembly is formed in the noted molding apparatus.
In yet another aspect, the present invention provides a molding apparatus for forming a golf ball with a plurality of deep dimples along its outer surface and at least two deep dimples accessible from the outer surface. The molding apparatus comprises a first mold half that provides a hemispherical first mold surface. The molding apparatus also includes a second mold half with a hemispherical second mold surface. Each of the first and second mold surfaces has a plurality of raised regions that form dimples along the outer surface of the golf ball. And, the first and second mold surfaces each include at least one outwardly extending protrusion that forms the at least one deep dimple along the outer surface of the golf ball. The outwardly extending protrusion has a height of from about 0.002 inches to about 0.140 inches.
The invention accordingly comprises several compositions, components and steps and the relation of one or more of such compositions, components and steps with respect to each other. Moreover, the invention is directed to articles possessing the features, properties, and the relation of elements exemplified in the following detailed disclosure.